EXTRACTION AND PURIFICATION OF PROTEASE FROM LOCALLY OKRA PODS (ABELMOSCHUS ESCULENTUS)

Abstract

This study aimed to extract, purify, and characterize the protease of local Okra Abelmoschus esculentus pods. The extraction process was conducted using ten extraction solutions with different pH and ionic strength values. Phosphate buffer solution with (pH 7, 0.05M, containing 2% sodium chloride) gave the highest activity which was (7.2 Unit/ml) as compared to other solutions, which ranged from 0.8-5.9 Unit/ml. The extracted enzyme purified by several stages. Being, precipitation by gradual addition of Ammonium sulphate from 20 to 85% saturation, then the precipitated enzyme was dialyzed and fractionated through DEAE-Cellulose (22X1.1cm), the enzymic fractions were pooled. The specific activity, purification fold and the enzyme yield values were 21.52 units/mg, 1.24 and 82.83% respectively. For further purification the enzyme fractions applied to G-75 Sephadex column (65x 1.5cm), the specific activity, enzyme yield and purification fold value were 98.82Unit/mg, 46.70%, 5.1, respectively .Electrophoresis analysis in the absence of SDS showed single band as indicator for enzyme purity. In conclusion, Okra pods could be one of natural source for proteases and this study recommended further studies regarding the adequate means for removal of the mucilage in order to increase the extraction efficiency.